Pennsylvania, United States
Brush Mountain is a stratigraphic ridge in central Pennsylvania, United States, running east of the Allegheny Front and west of Tussey Mountain. It lies along the southeast side of Little Juniata River and both sides of the Sinking Run, and is the westernmost ridge in its section of the Ridge-and-valley Appalachians. The western ridge line separates the Logan Valley from the Sinking Valley.
Brush Mountain lies entirely in Blair County. It runs from the water gap formed with Bald Eagle Mountain by the Little Juniata River at Tyrone, south to the Sinking Valley anticline fold near Altoona then north to the Canoe Valley syncline fold, where the ridge becomes Canoe Mountain, a distance of approximately 30 miles (44 km).
No major roads or rivers cross the ridge or run through gaps. Kettle Reservoir collects surface runoff from a small area in the fold, and the dam was made by filling in a small ravine. Kettle Road, a secondary road, also runs through the ravine near the dam to the Sinking Valley. A major power transmission line crosses the ridge twice, midway between the folds.
The Brush Mountain Ridge is popular with soaring birds and glider pilots ridge soaring along its slopes. This ridge is part of a chain of ridges that stretch south to Tennessee. The fold at the south end of Brush Mountain forms a gap in the chain, with the continuation of the ridge line 10km south on Dunning Mountain.